Malignant Melanoma: Causes, Symptoms, Diagnosis, Prevention and Treatment

It is the most aggressive and life-threatening skin cancer.

It develops in the cells that color the skin ( melanocytes ) and has a great tendency to spread to other parts of the body.

The cure rates depend to a large extent on the stage of the melanoma at the time of detection. The sooner it is detected, the better the chances of healing. Therefore, it is important to know what to look for and how to prevent it.

Who is at risk for malignant melanoma and how common is it?

Malignant melanoma occurs among all racial and ethnic groups studied adequately. The frequency of its appearance is closely related to the constitutive color of the skin and depends on the geographical area.

The incidence among dark-skinned ethnic groups is 1 per 100,000 per year or less, but among light-skinned Caucasians up to 50 and over in some parts of the world.

The highest incidence rates have been reported in Queensland, Australia, with 56 new cases per year per 100,000 men and 43 women. The estimated annual incidence of melanoma in the United States among whites, adjusted for the same standard population and for the same year (1987) is 14 and 11.

In northern Europe, the incidence is 5 per 100,000 in countries with low insolation. Malignant cutaneous melanoma is the cancer that increases most rapidly in whites.

The annual increase in incidence rates has been estimated between 3 and 7%, although mortality rates increase less rapidly. These estimates suggest a doubling of rates every 10-20 years.

The cumulative lifetime risk for melanoma is now of the order of 1: 25 in Australia and has been estimated at around 1: 75 in the United States by the year 2000. 1 in every 105 Americans born in 1993 will develop malignant melanoma in his life.

In contrast, the risk in 1935 was only 1 in 1,500, in 1960 1 in 500, and in 1980 1 in 250.

Malignant melanoma is now the fourth most common cancer in Australia and New Zealand, the seventh most common in the United States. UU And Canada, the tenth most common in Scandinavia and the eighteenth most common in the United Kingdom.

In contrast, for Africans and Asians, the annual incidence rate of malignant melanoma is 0.2 to 0.4 per 100,000 population, mainly affecting the palms, soles and mucous membranes.

The US figures UU suggest a statistically significant increase in thin tumors (<1 mm) in all age groups, except in men under 40 years. Thick tumors (> or = 4 mm) increased statistically significantly only in American males 60 years of age or older.

The male: female ratio is 1: 1 in the United States and Australia. In Europe, the incidence of sex shows a slight female preponderance in most countries.

The sex ratio for the incidence of melanoma varies with the incidence: it is higher in women than in men in areas of low insolation and low incidence rates.

Although we speak in general terms about the epidemiology of melanoma, this tumor has been subdivided into different types of tumors. Some of these subtypes have different epidemiological characteristics, both in incidence and mortality, and also in causative factors (for example, exposure to sunlight).

What causes malignant melanoma?

Environmental factors

Sun exposure : it has been reported that in areas with many hours of sunlight throughout the year, the occurrence of melanoma is the highest, which leads to the conclusion that sun exposure can be a risk factor in the sun. melanoma development.

There are also indications that skin that is not accustomed to sun exposure (like the skin of office workers) has a greater tendency to develop melanoma when it is intensely exposed to UV radiation than skin that is continuously exposed to sunlight (like the skin of outdoor workers).

A very important risk factor is sun exposure in childhood, especially when there is a history of sunburn early in life. Even sunburns in adulthood seem to be related to the development of melanoma.

Artificial ultraviolet light sources : several studies lead to the conclusion that artificial ultraviolet light can also be a risk factor related to melanoma. Such sources of light are mainly tanning beds that use high amounts of UVA.

Socioeconomic status: several studies have reported that melanoma is more prevalent in people of high socioeconomic status.

One explanation for this finding may be the fact that these people can afford vacations in areas of high intensity of UV radiation, as well as expensive outdoor pastimes, such as sailing, that increase the risk of melanoma due to intense sun exposure. .

Type of skin

The individual skin type (mainly type I and II skin) and the presence of multiple moles are important risk factors related to melanoma that must be taken into account when planning to be exposed to UV radiation. Therefore, take preventive actions.

Genetic factors

There seems to be evidence that a family history of melanoma in at least one first-degree relative could increase the risk of developing melanoma. In about one third of patients with melanoma, a genetic abnormality has been reported.

There are also some rare genetically determined disorders or diseases of the skin that can increase the risk of developing malignant melanoma.

Diagnosis

There are several criteria that can lead to the diagnosis of malignant melanoma. The most important is the ABCDE rule:

  • A:  means asymmetry. The injury is asymmetric, which means that no matter where the injury is reflected, it will not be the same.
  • B: The mole or lesion has irregular edges.
  • C: means irregular colors. The mole or lesion is irregular in color, from light brown to dark brown, black, red, blue or white.
  • D: means diameter. A mole or lesion is suspicious if it measures more than 5 mm in diameter.
  • E: denotes elevation. The elevation of a mole or lesion can be a clue to make the lesion malignant.

Patient’s history

If an injury seems suspicious, the clue to a personal or family history of malignant melanoma can support an accurate diagnosis.

Dermatoscopia

This is a handheld device used by dermatologists for a thorough inspection of the top layer of the skin. It is absolutely painless. To get a better view, the skin will be pre-treated with oil before inspection.

Biopsy

If there is still a doubt after all the diagnostic tools have been used, a biopsy is recommended to establish an accurate diagnosis. If there is a possibility of malignant melanoma, the lesion will be removed for further microscopic examination. This procedure will require local anesthesia.

symptom

Since malignant melanoma can cause death and there are many different types and appearances, it is important that a dermatologist take a look at a mole or suspicious lesion to catch melanoma at an early stage.

The appearance of malignant melanoma can vary from a flat patch to a nodule or a warty lesion. Its color can vary from red, brown, gray to black tones.

It can appear on any part of the human skin, from the areas exposed to the sun to the soles of the feet, the palms of the hands, the nails, the genital and oral skin (mucosa).

At first, it usually grows in a horizontal direction being quite superficial, but depending on the type of melanoma it can begin to grow rapidly in a vertical direction at an early stage.

If the melanoma is advanced, it may begin to bleed and ulcerate. The more developed a melanoma is, the greater the risk of spread to other parts of the body.

How to prevent malignant melanoma

According to the risk factors of malignant melanoma, the following preventive measures are recommended.

Exposure to UV rays should be minimized. It is not advisable to take prolonged sunbathing, especially of non-acclimatized skins, as well as the use of tanning lamps. Children under three should stay in the shade.

Sun protection must be achieved with appropriate clothing. Wide-brimmed hats, shirts with long sleeves and sunglasses are recommended. Children should dress especially well when playing outside.

The use of adequate sunscreens is recommended. However, this should not lead to prolonged sunbathing, thinking that all risks have been ruled out with the use of sunscreens.

Sunburn should be avoided, especially in children.

If you already have several moles, you should examine your skin regularly. If you have a mole or suspicious spot, seek the advice of a dermatologist.

People with multiple moles, abnormal moles or a family history of melanoma should undergo a dermatologist to check their skin regularly.

Is it really a malignant melanoma?

There are many skin diseases that can resemble malignant melanoma. The fact that you have a rough spot on your skin does not mean you have cancer, however, it is something that should be taken seriously. If you have noticed a strange area of ​​skin, consult your dermatologist or doctor.

What can go wrong?

Malignant melanoma can ulcerate and have a tendency to infection. Melanomas can also spread to other parts or organs of the body at an early stage ( metastasis ).

In general, malignant melanoma metastasizes initially to the lymphatic system in the surrounding skin or regional lymph nodes. Subsequent internal organs, such as the lungs, liver, brain and bones, may be affected.

Treatment

Because malignant melanoma is the most dangerous and life-threatening skin cancer, you should consult a specialist and discuss immediate measures and treatment options with him.

But try to keep in mind that the choice of treatment depends on your individual situation. You can take into account different factors such as the size of the tumor, the thickness and the stage when choosing a treatment.

Surgical removal of the tumor

This treatment will require an anesthetic (local). In general, not only will the tumor be cut, but a safety margin of 1 cm (horizontally and vertically) will also be eliminated to ensure that no diseased tissue is missed.

If the tumor has already reached the lymphatic system, a surgical removal of the entire lymph node may be necessary to minimize the risk of the melanoma spreading to other parts or organs of the body.

If the melanoma has already spread to other organs of the body (eg, brain, liver), these tumors should also be removed if possible. If surgery is impossible, radiotherapy or chemotherapy could be appropriate treatments.

Radiotherapy

This therapy uses X-rays to destroy damaged cells. In general, the affected area must be treated several times to reach a dose that is effective, depending on the size and stage of the tumor. Therefore, the therapy can last several weeks.

Chemotherapy

This type of treatment uses chemicals that have a specific toxic effect on the cancerous tissue. Most anti-cancer drugs are given in the vein or muscle, some are swallowed.

Chemotherapy is usually given in cycles: a period of treatment is followed by a period of recovery, then another period of treatment follows, and so on. There are several chemotherapeutic substances available.

Individual factors such as the spread of the tumor, the affected organs and the general health of the patient determine the choice of therapy.

Immunotherapy

Immunotherapy is a therapy that helps support the immune system. Usually, the medicine called interferon alfa or interleukin-2 is injected under the skin.

This treatment can last for a long time (up to a year or even longer) and is often used in combination with surgical removal of the tumor, radiation therapy or chemotherapy .

Unfortunately, this therapy is linked to several disturbing side effects with flu-like symptoms, such as fever, drowsiness and nausea. Sometimes it can also cause a reduction of white blood cells, sometimes even red.

Dealing with skin cancer can be very scary, so seek the advice of a dermatologist who you trust and discuss openly with you every aspect of your illness.

What are the chances of being cured?

There are several factors on which the prognosis of malignant melanoma is based.

Tumor thickness

The thickness of a melanoma is measured in millimeters from the top layer of the tumor to the deeper invasive melanoma cell. Melanomas less than 0.75 mm thick have only a low metastatic risk, while tumors 3 mm or more thick present a very high risk.

Levels of invasion

These criteria are based on the depth of penetration in the layers of the skin and range from level one (tumor cells in the epidermis) to level 5 (tumor cells below the dermis). The 5-year survival rate decreases with the level. Level 1 or 2 has a survival rate of more than 90%.

Location

Melanomas in the extremities have a better prognosis than those in the head or trunk. Melanomas in the genital region have a poor prognosis, since they are often discovered late.

Gender

Women are statistically more likely to survive than men.

Other factors

The tendency to ulcerate, the presence of tumor cells in the blood vessels and the cellular activity of the tumor cells are also factors that help to make a prognosis.